With increasing development of high technology industries, electronics devices such as notebook computers, phones, digital cameras and the like are widely used in our daily lives. Conventionally, these electronic devices are coupled to the power source via the linkage of power cables or communicated with other electronic devices via the linkage of signal cables. In other words, power cables and signal cables are utilized as transmission media for transmitting power and signals, respectively. Since these cables have several meters in length, it is critical to gather these cables for storage. Recently, many cable winding devices have been proposed to wind cables for storage.
Please refer to FIGS. 1A and 1B. FIGS. 1A and 1B are respectively schematic assembled and exploded views illustrating the conventional USB cable adapter. The USB cable adapter principally includes a USB connector 10, a signal connector 11 and a cable winding device 12. The USB connector 10 is coupled to an electronic device having a USB interface (e.g. a computer host). The signal connector 11 is coupled to an electronic device having a signal connecting interface (e.g. a digital camera or a charger).
The cable winding device 12 is interconnected between the USB connector 10 and the signal connector 11. The cable winding device 12 includes a case 121, a reel disc 122, a roller 123, a spiral spring 124 and a cable 125.
The case 121 comprises a first case element 1211 and a second case element 1212. A spool 1213 is extended from an inner surface of the first case element 1211 for securing the reel disc 122 thereon. A longitudinal gap 1214 is cut through the spool 1213 for anchoring the spiral spring 124 onto the spool 1213 such that the spiral spring 124 is fixed between the first case element 1211 and the reel disc 122. In addition, a confining groove 1215 is formed in an inner surface of the second case element 1212 such that the roller 123 is moveable along the confining groove 1215 after the first case element 1211 and the second case element 1212 are combined together.
The reel disc 122 is rotatable for winding the cable 125. A channel 1221, a guiding groove 1222 and a curved trough 1223 are formed in the outer surface of the reel disc 122. The guiding groove 1222 is disposed adjacent to the curved trough 1223 for anchoring the roller 123. The curved trough 1223 is disposed adjacent to the guiding groove 1222 and in communication with one end of the channel 1221 for restraining the movable range of the roller 123.
One end of the cable 125 is coupled to the USB connector 10, the other end thereof is coupled to the signal connector 11, and the intermediate portion thereof is wound inside of the reel disc 122. In response to pulling forces exerted on the USB connector 10 and the signal connector 11, the reel disc 122 and the spiral spring 124 are rotated counterclockwise such that the roller 123 moves in the channel 1221 toward the curved trough 1223. At the same time, the spiral spring 124 is being deformed. A sudden release of the pulling forces will cause the roller 123 to move in the guiding groove 1222 such that the reel disc 122 stops rotating and the cable 125 is locked. In other words, a user can lock the cable 125 by releasing the cable 125 after a desired length of the cable 125 has been pulled from the reel disc 122. Again, a continuous pulling operation of the cable 125 from the locked position will cause the roller 123 to move from the guiding groove 1222 to the channel 1221. Eventually, a release of the cable 125 causes the roller 123 to move in the guiding groove 1222 again for locking.
For rewinding the cable 125, the use may slightly pull the cable 125 to cause the roller 123 to clear from the guiding groove 1222. Next, a release of the cable 125 causes the compressed spiral spring 124 to release its stored energy to rotate the reel disc 122 clockwise. As a consequence, the cable 125 is completely rewound on the reel disc 122 if no stopping action is taken.
Although the cable winding device 12 can wind the cable 125 for storage, there are still some drawbacks. For example, the roller 123 has a relatively small size and is usually made of metal. During the process of assembling the cable winding device 12, it is difficult and troublesome to put the roller 123 on the correct position. Under this circumstance, the roller 123 of the cable winding device 12 is possibly lost if the installation of the roller 123 is improper. Moreover, the process of manufacturing the metal roller 123 also increases the cost of the cable winding device 12.
Therefore, there is a need of providing an improved cable winding device in order to obviate the drawbacks encountered in the prior art.